DALLAS -- Top union officials and player agents are discussing the possibility of withholding prospects from the NFL Scouting Combine and 2011 NFL Draft activities, sources said Friday, with the league's collective bargaining agreement expiring March 3.

NFL Players Association executive director DeMaurice Smith, who addressed the media Thursday, has been meeting and talking with prominent agents in recent weeks, including a sit-down Friday morning during Super Bowl festivities in North Texas.

According to several sources familiar with the discussions, central topics included the feasibility of withholding clients from the Feb. 23-March 1 combine in Indianapolis and boycotting draft activities in New York in late April, including the televised event itself at Radio City Music Hall. Several sources characterized the likelihood of a draft boycott as being much more likely or feasible than skipping the combine, but both options are being seriously discussed and considered by the union and agents.

"We have no knowledge of any such discussions," NFL spokesman Greg Aiello told The Associated Press in an e-mail.

Some agents expressed concerns that skipping the combine would hurt their clients' draft stock and earning potential.

"I'm not sure that would end up being fair to the kids," one source said, adding that it would be "more likely" that agents will band together to have clients boycott the draft events.

The AP confirmed the talks though a source and reported the union hopes such a boycott would disrupt teams' scouting of college players. Although it's unlikely to receive widespread support from agents, whose first duty is helping their clients be selected high in the draft, one prominent representative said he would instruct his clients to skip the combine if there was a consensus about doing so.

Agents already are upset about the rookie wage scale proposed by NFL owners for a new labor deal. Such a scale would severely limit the bargaining power for first-round picks in particular. The likelihood of anyone approaching Sam Bradford's league-record $50 million guaranteed in his rookie contract with the St. Louis Rams last year would be nil.

Teams will hold workouts for prospects throughout March and April leading up to the draft, and the NFLPA also is urging agents to consider boycotting those, according to The AP.

Smith has more meetings planned with small groups of agents later this month, and if the pace and progress of labor negotiations don't increase in coming weeks, the topics will continue to be considered within the NFLPA, sources said.